Factors influencing cognitive and neural representations contributing to memory

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Identifying conditions that help or hinder memory, and specifying the underlying brain regions implicated, are primary goals in the field of cognitive neuroscience. In collaboration with my trainees, we have generated and developed cognitive paradigms that extend our understanding of how memory works, and of its neural basis. My proposal lies at the intersection of the fields of cognition, memory, aging, and neuroimaging. The long-term goal is to develop a model specifying factors that influence both the quantity and quality of what can be remembered. In Aim 1 we will evaluate whether the number and type of memory traces, or codes engaged during encoding, predict the level of subsequent episodic memory. The number of traces will be manipulated by varying task instructions during encoding, that differ in terms of their engagement of motoric, semantic, generative, and pictorial processing. In Aim 2 we will evaluate the degree to which susceptibility to being forgotten is influenced by the nature of representation formed at encoding. Inferences regarding representational codes engaged will be determined by susceptibility to memory interference from multi-tasking conditions. In Aim 3 we will determine whether certain contexts can support memory by facilitating target representations during encoding. We will accomplish this by manipulating pre-existing familiarity, personal relevance, and emotionality of the visual context in which a target is encoded. For each aim, by comparing performance in younger adults to that in senior citizens with known deterioration is key brain regions, we will determine whether changes in neural integrity modulate observed effects on memory performance. This proposal builds on the idea that episodic memories are formed by the interaction of representations invoked during initial encoding (visual, motoric, semantic, emotional). Each representation encompasses a separate network, with its own behavioural properties, and neural substrates. It is the interaction of these that allows for rich episodic memories in humans. We will build a model offering greater predictive power, specifying factors and conditions that enhance retention of information. It will also highlight conditions in which memory can be disrupted, providing insight into the limitations of human cognitive processing. By explaining why certain factors influence memory, we will identify a means of compensating for interference effects. Such knowledge highlights ways in which memory can be ameliorated despite deficits associated with normal aging, and with multi-tasking environments which are ever more present in today's fast-paced world.